The present invention relates to a passive missile homing system, called "self-director", comprising at least three interferometric bases, each having two electromagnetic antennae disposed on the missile.
Infrared self-directors are already known. Their accuracy is very high and they may then advantageously guide a missile at the end of its flight path, close to the target. However, their range is relatively limited.
Electromagnetic self-directors of the above-mentioned type are also known. Their accuracy is not as good but their range is wide and they may advantageously take charge of the missile at a great distance from the target and guide it within the vicinity thereof.
However, in these known electromagnetic self-directors, the elaboration of the guidance orders is effected in two perpendicular planes. When the missile, to which they are fixed, rotates laterally, which is generally the case, there are losses of information when the polarizations of the bases are perpendicular to the polarization of the radiation to be received. Furthermore, there may also be a loss of the range of use, even in stabilized flight, in the case of reception interference, at one antenna or more, between the direct signal and the signal reflected from the ground or from the sea. This phenomenon may moreover also occur with circular polarization antennae which, all the same, risk being blind for receiving signals polarized in a reverse circular direction.
The present invention aims at palliating these disadvantages.